The present invention relates to dishwashers and, more particularly, to an interlock mechanism for a dishwasher which will automatically assure closure of the wash reservoir drain when the dishwasher door is closed.
The present invention relates to dishwashers of the type shown in U.S. Pat. No. 3,911,943, issued Oct. 14, 1975, to Athey et al and assigned to the assignee of this application. This type of dishwasher is used generally in a commercial environment, such as a restaurant, in which a relatively large number of dishes or other items are to be washed. The dishwasher cabinet defines an internal chamber into which racks of the items to be cleaned are placed. The lower portion of the chamber defines a reservoir into which washing fluid containing a detergent or other cleaning agent is loaded before a washing operation is begun. The dishwasher further includes a pump and spray arrangement which pumps the washing fluid out of the reservoir and sprays it onto the dishes. The washing fluid is then collected in the reservoir. This washing fluid may be used to wash a number of loads of dishes before the reservoir is drained and charged with fresh washing fluid.
During the rinse cycle, fresh water is sprayed onto the dishes by a separate rinse spray arrangement and then collects in the reservoir. A standpipe in the reservoir cooperates with the reservoir drain to insure that the fluid level in the reservoir does not exceed a predetermined level. The standpipe normally covers the drain opening in the bottom of the reservoir but may be raised to permit the reservoir to be drained completely.
The dishwasher disclosed in the Athey et al patent has a lever mounted on the exterior of the cabinet by which the standpipe may be moved into and out of engagement with the reservoir drain. If the dishwasher operator should forget to move the standpipe into its lower position and thus effectively close the reservoir drain prior to charging the reservoir with washing fluid, the washing fluid added to the reservoir would simply flow out the reservoir drain and no fluid would be available for washing the dishes.
It is clear, therefore, that a need exists for a simple, reliable interlock which will insure that the wash reservoir drain is closed when the dishwasher is operated.